Tach 10 pole to 20 pole converter.

[Bad_az_s10]

Re: Tach 10 pole to 20 pole converter.

note:.. today, the tach starts at 2100 at idle, and goes up to 5000, it is definately reading too high now.. I Did turn the screw yesterday. Oh well, two more tries, I'll get it right, I suppose!

Bob

So what concerns me here is the tach should have been set correctly from the factory. I am not sure why it just stopped working. Unless someone was messing with it I would suspect mechanical failure. There are a couple of things that COULD go wrong and cause the tach to go crazy. 1) the rectifier could be shot. 2) the stator could be on its way out. 3). the gauge could be on its way out. Unfortunately all of the above will require further investigation. Of coourse without being able to troubleshoot I am just throwing a variety of things that COULD be wrong and I am sure there are many more. As far as setting the screw I would use an external induction style tach and set teh two until they read the same. You can get a tach\hourmeter style one for like $15 bucks or one used for tuning engines for like $50.

 

[BobList]

Re: Tach 10 pole to 20 pole converter.

Unless someone was messing with it

I would be the one who had it out! I took it out, and replaced the glass... I'm sure that's when I hit the pole screw.. the guy I bought the boat from said it worked fine.. I took it out before ever having it on the water to be able to read above fast idle speed.

Bob

 

[tlsintko]

Re: Tach 10 pole to 20 pole converter.

Hi all. I'm selling a 20 pole tach from my 1986 Force 125 on eBay. The auction ends May 17. http://cgi.ebay.com/ebaymotors/US-M...6307317QQptZBoatQ5fPartsQ5fAccessoriesQ5fGear

If the link doesn't work, just search eBay for "Force Tachometer" or item #270746307317

The tach works fine, but I had to retire the outboard due to a lost cylinder. Then I re-powered with a Johnson 150, so I had to replace the tach too. Here's a picture.

 

[manndl]

Re: Tach 10 pole to 20 pole converter.

I have a few tachs with 20 pole settings available, for those that might be interested. They are NOS (new old stock). I have two styles available: 7k RPM black face/bezel, red needle (OMC design), and 8k RPM white face/bezel, black needle (Faria design). If interested, contact me, and I can list them on eBay with pictures.

 

[fucawi]

Re: Tach 10 pole to 20 pole converter.

frank has already told you that not all the 20 poles output to the tacho...anyway they work in pairs and the output to the tach is from the AC side of the rectifier..It gives a series of rectified positive pulses to the tacho ( full wasve rectifeid with every other pulse removed) Its only called 20 pole because it goes on a outboard with 20 poles..to make it simple for idiots that dont understand outboard alternators ......